No, that's not science. You also need an energy source, which can be organic material in the water.xyz wrote:Here's a little science:
humidity + heat + darkness = mildew/mold
(if not cleaned)
Think about your shower.
You also need available nitrogen, which can NOT be airborne nitrogen for mold or fungus, or probably for any disease organism. You can't make protein without nitrogen.
There are other nutrients that are needed.
Algae might be able to use light for their energy source, but they can't fix nitrogen, so they need a source of nitrogen.
Some forms of bacteria and maybe some other organisms can fix nitrogen, but they would need some form of food in the water.
Distilled water reduces the potential for germ growth because there is little or no food or trace nutrients (available nitrogen and other chemicals) in the water.
Your shower has lots of other contaminants such as skin cells, body oils, etc. on it. Plus the tap water in the shower spray has organic material and minerals in it.
In the CPAP humidifier and tubing, there will be SOME "germ food." The dust that gets through the filters has various germ nutrients in it in small quantities. There's some small amount of germ food even in distilled water because it's not 100.0000% pure. Some germs might be able to get some sustenance by eating the plastic, but the manufacturers try hard to no let this happen. You can also contaminate the tubing and tank yourself when cleaning or handling it. I wonder if some types of soap may be germ food when sufficiently diluted.
Distilled water makes it much harder for germs to grow, but there's still some risk.
Personally, I'm not that worried. I use distiled and wash the tank and hose every week. I wash the tank in the dishwasher, and rinse the hose with hot water. I have two tanks and several hoses. Every week, when I wash them, I put the clean parts away to sit dry for a week, and use the parts that I washed the week before. I figure that sitting dry for a week will help keep germ growth down. I also dry my freshly washed hose on an old CPAP machine that I don't use any more.